the solution described below turns out to have its flaws and is not really recommended — have a look at the recently posted update for a better solution!

simple build tool 0.7.5 comprised the jetty and webapp functionality — version 0.10.0 (sbt10) no longer does so, instead you have to pull in the sbt webplugin. one feature of sbt7.5’s webapp support that we used heavily was the ability to run jetty out of the source tree instead of the exploded temporary WAR file: